Propeller for boats.



D. H. SINCLAIR.

PROPELLER FOR BOATS.

APPLICATION FILED SEPT. 10. i915- HENEWED JUNE 8. 19l6.

l ,1 QZQJ Patented Sept. 5, 1916.

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D. H Sine?" DAVID H. SINCLAIR, OF NEW ORLEANS, LOUISIANA.

PROPELLER FORBOATS.

Specification of Letters Patent.

Application filed. September 10, 1915, Serial No. 50,032. Renewed June8, 1916. Serial No. 102,599.

To all whom it may concern:

Be it known that 1, DAVID H. SINCLAIR, a citizen of the United States,residing at New Orleans, in the parish of Orleans and State ofLouisiana, have invented new and useful Improvements in Propellers forBoats, of which the following is a specification.

This invention relates to a novel and improved propeller for boats, andits primary object is to provide a propeller which may be applied to anyordinary form of row boat or other small boat, for propelling the samethrough the water.

A further object of the invention is to provide a propeller which may bemanually operated to furnish proper propulsive power, and which embodiesa propeller blade mounted to swing in an arc in a general directionlongitudinally of the boat, and which is adapted on its return motion tofold or close to a non-resisting position, so as to establish afeathering action.

A still further object of the invention is to provide a propellingdevice, which, if desired, may also be employed as a rudder.

The invention consists of the features of construction, combination andarrangement of parts herein fully described and claimed, reference beinghad to the accompanying drawing in which Figure 1 is a side elevation,partly in section of the stern portion of a boat, showingthe applicationof the invention. Fig. 2 is a top plan view of the same. Fig. 3 is adetail view showing in modified form the propeller blade.

In carrying my invention into practice, I provide a supporting bracket 1of convenient size to rest upon the gunwale at the stern of any suitableform of small boat 2, such as a row boat, which bracket comprises a baseplate 3, preferably having a central portion a of circular form, andspaced parallel cheek plates 5 rising from said base plate, the saidcheck plates being provided with forwardly and rearwardly extending arms6 and 7. One or more bolts or other suitable fastenings 8 pass throughthe base plate and secure the bracket to the boat 2. If desired, asingle bolt may be employed at the center of the circular portion of thebase plate, which may serve as a pivot on which the bracket may swingfrom side to side to change the position of the propelling device andadapt it to serve as a rudder, as hereinafter described.

Pivotally mounted at its upper end upon a pm Qpxtending between the arms7 is a longitudinally swinging arm or lever 10, which is movable withina prescribed are substantially in line with the longitudinal center ofthe boat. This swinging arm or lever 10 carries at its lower end apropeller 11, the said propeller being in the form of a flat blade orplate having rearwardly extending flanges 12 disposed on opposite sidesof the lower end of the lever 10 and pivotally connected therewith by apin or bolt 18, the lower end of the lever 10 being formed to provide aninclined bearing or abutment surface 14-.

At a point below its upper end the lever 10 is coupled by areciprocating connecting rod or bar 15, which is movable through theguide space or channel between the plates 5 and is pivotally connectedat its forward end with the short arm 16 of a bell crank operating lever17, having a comparatively long operating arm 18, said lever being pivoted at the angle of intersection of its arms with and upon a pivot pin19 extending between the bracket arms 6. By this mode of mounting thelevers and connecting rod it will be seen that they move in guidingconnection with and between the plates and arms of the bracket 1 andhence are held fromv lateral or sidewise motion on their pivots, thuseliminating a large amount of the wear and tear which would otherwise becaused by the tendency of the parts, espe cially when loose, to wabbleon their pivotal connections.

The power arm or operating arm of the lever 19 may be of any suitablelength, and it may be operated by one or more of the occupants of thecraft, said arm being oscillated or vibrated up and down, by which aback and forth oscillatory motion will be imparted to the arm 16, thusreciprocating the rod 15 and swinging the lever 10 back and forth, aswill be readily understood. It will be evident that the flanges 12 guidethe propeller blade 15 in its swinging movements and hold it fromlateral motion, and that when the lever arm 18 is depressed the lever 10will be swung rearwardly on its working motion, while on the upwardmovement of the arm 18 the lever 10 will be swung forwardly on itsinactive or return motion. When the blade 11 is at the limit of itsreturn motion, it is swung downwardly and forwardly to an extent limitedby the abutment 14 under the water pressure, but as the arm 10 swingsrearwardly the pressure of the water on the rear'face of the bladeforces it upwardly and forwardly to; a folded or closed position inwhich it bears against and is backed or braced by the arm 10, so that itwill give a direct propelling effect against the surface of the Wateruntil it reaches the limit of its working motion, as shown in dottedlines in Fig. 1. 'On the return motion of the lever 10 and blade 11, thelatter is swung rearwardly and downwardly on its pivotal connection toan open and substantially nonresisting position, in which it travelsedgewise through the water, thus avoiding undue resistance to its returnmotion and enabling a person to operate the propeller with full 'forceand for long periods without undue fatigue.

It will be evident from the foregoing description that by vibrating oroscillating the lever 18 in a vertical plane a rapid'and powerful backand forth motion may be imparted to the propeller, so as to force theboat with considerable speed through the water, and it will be evidentthat, if desired, the propeller maybe adapted to serve as the additionalfunction of a rudder by swinging the device laterally in eitherdirection on the bolt 8 as a fulcrum and thus disposing the propeller toeither exert a resistance at one side of the craft or to set up apropeller action at an angle to give the desired steering motion.

While the form of propeller shown in Figs. 1 and 2 is preferred, amodified structure may be employed in some cases, and such a modifiedstructure is shown in Fig. 3, wherein the propeller blade 11 isillustrated as being vertically divided and consisting of sections 11and 11 provided at their adjacent edges with knuckles 20 engaging apintle pin 21 disposed within a recessed portion of the lever arm 10.With this construction the hinged sections of the propeller blade areadapted 0n the working motion to lie in longitudinalor edgewisealinement with each other, and to form a Copies of this patent may beobtained for five cents each, by addressing the broad abutment orpropelling surface but on the return motion of the lever 10 the pressureof the water causes the blade sections 11 and 11 to unfold-rearwardlyuntil substantially in parallel relation, thus producing a featheringaction which diminishes its resistance on its return stroke.

I claim 1. A propeller for boats comprising a bracket composed of spacedplates and forwardly and rearwardly extending arms, an operating leverpivotally connected with the forwardly extending arms, a swinging leverarm pivotally connected with the rear bracket arms, a featheringpropeller blade carried by the swinging lever arm, and a connecting rodcoupling the said operating lever to the lever arm and slidably movablebetween the spaced plates of the bracket.

2. A propeller for boats comprising a base plate pivotally mounted toswing at an angle to the keel line of the body, a bracket carried bysaid base plate and composed of spaced side plates and forwardly andrearwardly extending arms, a bell crank operating lever pivotallyconnected with the forwardly extending arms, a swinging lever armpivot-ally connected with the rear bracket arms, a feathering propellerblade carried by the swinging lever arm, and a connecting rod couplingthe bell crank operating lever to the lever arm and slidably movablebetween the spaced side plates of the bracket.

A propeller for boats comprising a bracket composed of spaced plates andforwardly and rearwardly extending arms, a bell crank operating leverpivotally connected with the forwardly extending arms, a swinging leverarm pivotally connected with the rear bracket arms, a pivoted foldingpropeller blade carried by the swinging lever arm, and a connecting rodcoupling the bell crank operating lever to the lever arm and slidablymovable between the spaced plates of the bracket.

In testimony whereof I aliix my signature in presence of two witnesses.

. DAVID H. SINCLAIR.

Vitnesses J OI-IN COOK, A. FISCHER.

Commissioner of Patents,

Washington, D. C.

